Field of the Invention
The invention relates to an integrated circuit on a semiconductor chip in which a temperature sensor is integrated and a method for heating the circuit.
Integrated circuits work in a very wide temperature range. If the circuit is required to work perfectly at very low temperatures as well, individual specimens of the circuit must also be tested at low temperatures at least by random sampling. But this additional selection substantially decreases the yield of usable circuits. Such a problem occurs particularly with memory modules such as DRAMs.
It is accordingly an object of the invention to provide an integrated circuit with temperature sensor and a method for heating the circuit that overcome the hereinafore-mentioned disadvantages of the heretofore-known devices and methods of this general type and that has a high operational reliability even at low temperatures.
With the foregoing and other objects in view, there is provided, in accordance with the invention, an integrated circuit on a semiconductor chip, including an integrated temperature sensor detecting a temperature of the semiconductor chip and providing a measured temperature signal, a structure of electrical conductors, and a special circuit device connected to the integrated temperature sensor and to at least some of the conductors, the special circuit device generating, dependent upon the measured temperature signal, current flow through the at least some of the conductors when the detected temperature falls below a given temperature value.
In the inventive integrated circuit on a semiconductor chip, at least one temperature sensor is integrated on the chip together with the circuit, which sensor delivers a temperature-dependent measuring signal or at least emits a signal when the chip temperature falls below a specific prescribed value. For this eventuality, a special circuit device is provided on the chip, which brings about a current flow through a provided structure of electrical conductors, thereby generating heat in a sufficient quantity to hold the temperature of the integrated circuit above a prescribed minimum temperature. Not only does such an integrated circuit increase the yield of chips that function perfectly at low temperatures, but it also can be used at lower temperatures than have been possible hitherto.
The structure of electrical conductors is simply to be configured such that the current flowing through generates a sufficient quantity of heat the ohmic resistance of the conductor so as to achieve the desired thermal effect. These conductors can be the conductive tracks that are provided on an integrated circuit anyway, these being conductively connected to the special circuit device for generating the current flow as needed.
In a semiconductor memory, the conductors of individual memory blocks (banks) that are not needed for a presently occurring store or write operation can be utilized. The conductors are the address lines over which the stored signals are sent to the memory cells or read therefrom. Which banks of the memory chip are currently available for generating a heating current is determined by the drive circuit of the memory. The special circuit device is interconnected, as required, with the conductors of the deactivated memory blocks, which are not being used at present.
In accordance with another feature of the invention, there is provided a memory having operating states, subregions, and address lines, the conductors forming at least some of the address lines in a respective one of the subregion, the at least some of the address lines connected to the special circuit device, preferably, according to at least one of the operating states of the memory.
In accordance with a further feature of the invention, there is provided a memory cell field having a margin and dummy cells are disposed at the margin and form at least some of the conductors.
In accordance with an added feature of the invention, there is provided a margin, the conductors being formed by dummy cells at the margin.
In accordance with an additional feature of the invention, the special circuit device is programmed to drive the memory and to modify the operating states of the memory.
In accordance with yet another feature of the invention, the special circuit device is programmed to drive the memory and to modify operating states of the memory.
In accordance with yet a further feature of the invention, the special circuit device is to be driven by external commands to modify the operating states of the memory.
In accordance with yet an added feature of the invention, the special circuit device is programmed to drive the memory with activate and precharge commands and to modify the operating states of the memory.
In accordance with yet an additional feature of the invention, the special circuit device to be driven by external activate and precharge commands to modify an operating state of the memory.
In accordance with again another feature of the invention, the special circuit device generates signals in at least one given operating state of the memory effectuating a cutoff of current flow in at least some of the conductors when current is flowing through the conductors.
In accordance with again a further feature of the invention, the integrated circuit has operating states and the special circuit device generates signals effectuating a cutoff of current flow in at least one of the operating states in at least some of the conductors when current is flowing through the conductors.
With the objects of the invention in view, in a semiconductor chip, there is also provided an integrated circuit including an integrated temperature sensor detecting a temperature of the semiconductor chip and providing a measured temperature signal, a structure of electrical conductors, and a special circuit device connected to the integrated temperature sensor and to at least some of the conductors, the special circuit device generating current flow through the at least some of the conductors when the detected temperature falls below a given temperature value.
With the objects of the invention in view, there is also provided a method for heating an integrated circuit, including the steps of providing a semiconductor chip having a structure of electrical conductors, integrated temperature sensor, and the integrated circuit, detecting a temperature of the semiconductor chip with the integrated temperature sensor and generating a measured temperature signal, connecting a special circuit device to the integrated temperature sensor and to at least some of the conductors, and generating, dependent upon the measured temperature signal, current flow with the special circuit device through the at least some conductors when the detected temperature falls below a given temperature value.
Other features that are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in an integrated circuit with temperature sensor and a method for heating the circuit, it is, nevertheless, not intended to be limited to the details shown because various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.